Day 132: Angular Motion Representations, Whiteboarding, & Stoich Problems

AP Physics 1: Angular Motion Representations

We started by discussing yesterday’s activity to introduce angular velocity; there was some great debate about which dot on the disk was moving the fastest, which lead exactly where I wanted it to. Afterward, students worked on some problems translating between different representations of angular motion. Students fell very easily back into the kind of thinking we’d done with linear motion, which made the problems a breeze.

Physics: Whiteboarding

We finished going over the standing wave problems and took a quiz on the topic.

Chemistry Essentials: Stoichiometry Problems

Students worked some stoichiometry problems that included polyatomic ions. Most students are doing very well with the problems, which has me very optimistic about tomorrow’s quiz.

Day 129: Problems, Standing Waves, & Problems

AP Physics 1: Torque Problems

I was much more teacher-directed today than I typically shoot for. I ended up walking students through how to approach balanced torque problems; students were pretty into the idea that they can pick a pivot point for the problem that lets them solve for different quantities. We had a few minutes at the end for some whiteboarding. While students aren’t confident yet, I think they are doing just fine on balanced torques.

Physics: Standing Waves

We went through a guided discussion to get at the patterns for standing waves using first a wave generator with a string, then a singing rod, and ending with a tuning fork. When there were some good points for small group discussion, I had students work in their packets, but I think it would have been better to have them use whiteboards.

Chemistry Essentials: Stoichiometry Problems

Students worked some stoichiometry problems. We stuck to whole number ratios so students could draw particle diagrams as a tool to work through the problems.

Day 150: Final Project Work, Whiteboarding, & Quiz

Its been a rough week, and I spaced out on taking pictures today.

AP Physics: Final Project Work

Students finalized their proposals for the final projects. A lot of students this year are interested in the idea of digging into a movie scene to see if the physics is realistic. I got out my copy of James Kakalios’ The Physics of Superheroes for interested students to take a look at since Kakalios does something similar with comic books.

Physics: Whiteboarding

Students whiteboarded selected problems from yesterday before taking their quiz on sound. A lot of students had trouble with a problem to determine whether an organ pipe is open or closed given the first three frequencies that produce standing waves; I think they weren’t connecting the sketches of standing waves we’ve been doing to the written problems.

Chemistry Essentials: Quiz

Students took a quiz on reaction types, as well as a second attempt at limiting reactant stoichiometry. Glancing over the quizzes, many of my stronger students relied heavily on particle diagrams, which is great to see. I need to keep working on helping all of my students connect those diagrams to the math.

Day 149: Final Project, Problems, & Whiteboarding

AP Physics: Final Project

Students continued refining their proposals for the final project. Lots of students have ideas I’m really excited to see. A few students are working on ideas where it may be interesting to look at dissipated energy, so we got out the infrared camera to play a little. It turns out some glasses block a lot of IR.

ir selfie

Physics: Problems

Students worked on some sound wave problems. Things seem to be clicking for most students.

Chemistry Essentials: Whiteboarding

We spent some time talking about the observations students made during yesterday’s lab and drawing explicit connections to the equation for the chemical reaction. My students don’t have a great sense for what certain chemicals look like, so it ended up being more teacher directed than I’d like. Students also weren’t sure when a chemical will show up as a gas, since I’ve dropped the subscript g in order to simplify the equations we’re looking at, but I’m not sure that is a useful simplification.

After the discussion (or, more accurately, lecture with student responses), student whiteboarded some limiting reactant problems. The students who were engaged made some good progress.


This student asked me if I could write the symbols for sodium hydride and bromine oxide

Day 147: Test Day, Board Meeting, & Reaction Types

Today was a strange day; a lot of students were impacted by some unexpected news last night.

AP Physics: Test Day

Today was the AP Physics 1 exam. However, we were able to give students the option of taking the make-up exam later this month and the majority of my students took this option. In my morning section, I’d planned to make today a game day for students to relax and have some fun before the exam, and decided to stick with that in both sections. Most students opted for some puzzles the calc teacher loaned me.


Physics: Board Meeting

Students whiteboarded their results for yesterday’s speed of sound lab. The data came out very nice in both classes. Afterward, we had time for students to get the snakey springs out to start exploring wave superpositions. Even though I didn’t mention it in the prompts, one group got curious and tried to figure out whether the pulses reflect or pass through each other.

sound wb.jpg

Chemistry Essentials: Reaction Types

Classroom management gets tricky during labs with this class, so I decided to push back the lab I’d planned for today. Instead, I moved up a worksheet for students to practice identifying reaction types from chemical equations. One student was excited to show me an alternative representation she came up with for balancing chemical equations; its always exciting to not only have students coming up with their own ways of thinking about problems, but proud enough of their work to want to show it off.

bal shortcut.jpg

Day 146: Multiple Choice, Speed of Sound, & Whiteboarding

AP Physics: Multiple Choice

With the AP exam tomorrow, I asked students which of several options they thought would be most useful and both classes requested we use Plickers to review multiple choice. Most students weren’t at their most focused today, but there were still some good discussions.


Physics: Speed of Sound

Students worked on the classic speed of sound lab. Since several labs lately have been pretty rough, I structured the pre-lab discussion more like the way I do in September to get back to basics of experimental design and made sure sketches of the set-up made it onto the main whiteboard. I also took advantage of the fact that students have made other wavelength vs. frequency graphs to emphasize that students should graph as they go to see if their results make sense. My 1st hour got a lot farther than my 5th, but their slopes are coming out very nicely.

speed of sound.jpg

Chemistry Essentials: Whiteboarding

The limiting reactant quiz last week did not go as well as I hoped, so we spent some time today whiteboarding a problem, emphasizing the role of particle diagrams. The students who were engaged seemed to get a lot out of the whiteboarding.

chem lr wb.jpg

Day 144: Choice Labs, Tuning Forks, & Reaction Types Reading

AP Physics: Choice Labs

Today, I set up kits for a variety of labs targeting different topics and had students pick which labs to complete. I also had one last set of free-response problems, and most groups picked to work on those rather than the labs. I think they see a clearer link between the written problems and the test than they see between the labs and the test. In one of my classes, several students left their lab group to go talk to a peer they see as an expert on a topic they wanted to work on, which was awesome.

Physics: Tuning Forks

Students did a lab playing with tuning forks and singing glasses to start building some ideas about sound. This was the most animated I’ve seen my students this tri, which was a lot of fun. Students also made some great observations; one noticed that when a tuning fork vibrates in water, the water shoots mostly to the sides and use that to help justify which way the tuning fork vibrates.

tuning forks.jpg

Chemistry Essentials: Reaction Types Reading

We got out the textbooks for students to start building some vocabulary for different types of reactions. I could tell students weren’t latching on to the vocabulary in the same way they do when we establish a concept before the language. Tomorrow, we’ll be doing an activity using Legos to practice recognizing the different reaction types, but I wonder if there is a way I can rework the Lego activity to put it first and motivate naming different types of reactions.

Day 135: Closed Pipe Waves & Porosity

AP Physics: Closed Pipe Waves

I started class by showing students a few examples of sound waves in open pipes to establish that standing sound waves follow the same rules we saw last week for a standing wave on a string fixed at both ends. Then, I had students use our speed of sound materials to find the pattern for sound waves in a closed pipe. To keep the follow-up discussion short, I went back to standing at the front of the room and asking students to share their general results. In one class, students spontaneously started answering my questions by pointing out a lab partner who’d said something interesting and asking them to share, which lead to some students who don’t always speak up in whole-class settings getting their voices heard, which was pretty cool.

standing wave (1).jpg

Earth Science: Porosity

Students designed their own experiments to compare the porosity of sand, gravel, and Play-Doh. Students needed a little more scaffolding on how to measure the amount of water absorbed, but they ended up with nice results overall. Tomorrow, we’ll spend some time connecting these results back to the structure of aquifers.


Day 82: Board Meeting & Experimental Error

AP Physics: Board Meeting

Students whiteboarded their results from the cart explosion lab to start building the momentum transfer model. I can tell its been a while since we’ve done a true model-building lab, so students needed some reminders about how to linearize or “translate” y=mx+b, but those skills came back pretty quickly. I did wish I’d had students linearize a bigger variety of graphs so far this year; a lot of students went straight to squaring a variable, so I may want to think about how to get more variety early in the year next year.

When we discussed the lab, a few groups had linerized based on a quadratic relationship and had a fairly large intercept. To decide whether the large intercept made sense, one student suggested exploding the plunger cart off empty space to get a mass ratio of zero and show the velocity ratio must also be zero.


Physical Science: Experimental Error

We spent some time discussing yesterday’s speed of sound lab, focusing on error in measurements. I tried having students stand in different parts of the room based on how they thought frequency affects the speed of sound. When students were picking their spots, there was a lot of great conversation, including some contrasting frequency and speed, which was a great side effect. As we talked about error and what it means for values to be “close”, I had a lot of students ask to move because they changed their mind about what the answer should be.

Day 81: Exploding Carts & Speed of Sound

AP Physics: Exploding Carts

Students worked on the exploding carts lab to build momentum. I rushed through the intro in my 4th hour since they didn’t have a chance to start collecting data, and students struggled with some pieces as a result, especially with what it looks like to graph ratios instead of numbers. I could also tell it’s been a while since we did a true model-building lab; a lot of groups got very focused on specific numbers, rather than the overall pattern. I need to do a better job of making sure we do those kinds of labs regularly.


Physical Science: Speed of Sound

Students used a closed pipe to find the speed of sound. As a result of some of the changes I made this year, students had a much better conceptual understanding of the lab than in the past. The calculation to get the speed didn’t quite seem to fit, though.

While students worked, I conferenced with students about their progress on a project. I met with every student, whether or not they had a draft. I really liked getting a chance to talk to each group; I think it gave a few students a push to stop procrastinating.